Rates of women who are opting for preventive mastectomies, such as Angeline Jolie, have increased by an estimated 50 percent in recent years, experts say. But many doctors are puzzled because the operation doesn't carry a 100 percent guarantee, it's major surgery -- and women have other options, from a once-a-day pill to careful monitoring.

The study, conducted in the Netherlands, found more children with autism living in Eindhoven, a region known for its IT sector, than in two other regions with fewer IT businesses.

The findings may apply to other IT-rich regions, including California's Silicon Valley, said study researcher Simon Baron-Cohen, director of the Autism Research Center at the University of Cambridge in England.

The findings are in line with the "hyper-systemizing" theory of autism. This theory proposes that people with autism have a strong desire to understand the workings of systems, the researchers said. Such skills are valued in IT-related fields, including engineering, physics, computing and mathematics.

The results of the new study could be explained by adults gravitating toward jobs in IT because they have a talent in systemizing. They do not necessarily have autism themselves, but they pass down autistic traits to their children, who may develop full-blown autism, Baron-Cohen told MyHealthNewsDaily.

The findings may explain why genes for autism persist in the population, Baron-Cohen said. The study was published online June 17 in the Journal of Autism and Developmental Disorders.

Baron-Cohen and his colleagues surveyed schools in three different regions of the Netherlands: Eindhoven, Haarlem and Utrecht-City. They asked the schools how many children were enrolled and how many had autism. For comparison, they also asked how many had two other developmental disorders : attention deficit hyperactivity disorder and dyspraxia, which is a motor skills disorder. A total of 62,505 children were included.

In Eindhoven, there 229 children with autism for every 10,000 children. This was significantly higher than the other two regions (84 per 10,000 in Haarlem, and 57 per 10,000 in Utrecht). The prevalence of the other two conditions was similar in all the regions.

The researchers plan to conduct a follow-up study to validate the diagnoses of autism provided by the schools, Baron-Cohen said.